Method and apparatus for winding coils on bobbins



Nov. 12, 1968 N, D. LAWLESS ETAL 3,409,980

METHOD AND APPARATUS FOR WINDING COILS ON BOBBINS Filed Dec. 27, 1965 2 Sheets-Sheet 1 IN VENTORS ATTOR EY 1968 N. D. LAWLESS ETAL 3,409,930

METHOD AND APPARATUS FOR WINDING COILS ON BOBBINS 2 Sheets-Sheet 2 Filed Dec. 27, 1965 a IN VENTORS United States Patent O I 3,409,980 METHOD AND APPARATUS FOR WINDING COILS ON BOBBINS Norman D. Lawless and Noel A. Triaca, Flint, Mich., as-

signors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Dec. 27, 1965, Ser. No. 516,327 3 Claims. (Cl. 29605) ABSTRACT OF THE DISCLOSURE The construction of gages of the type having coils of wire wrapped around a bobbin and connected to terminal posts. The bobbins are mounted on a turntable which indexes the bobbins through a sequence of stations where the various stages of construction take place. The coils are wound and wire is looped over the terminal posts at the first station. The wire is cut at a second station while the bobbin in a third station intermediate the first and third maintains tension in the wire.

Summary of the invention This invention relates to the assembly of electrical gages and more particularly to a method of winding coils of wire onto bobbins such as those used in electrical gages and to apparatus for carrying out the assembly method.

The assembly of an electrical gage of the magnetic flux producing type involves the winding of one or more coils of conductive wire onto a bobbin having two or more electrical terminals. Electrical connections between the wire and the terminals are made during the assembly to facilitate later installation of the gage in, for example, an automobile instrument panel, where further electrical connections between the gage coil or coils and an external source of electrical signals are made.

According to the present invention, a method of winding wire on a bobbin is proposed. This method is particularly suitable to automated and rapid production of substantially fully assembled gages of the class described above.

In general, the inventive method contemplates a continual process of coil winding and connecting wherein each bobbin to be wound is advanced through a series of stations at which various functions are performed in such a manner as to eliminate the necessity of breaking the supply of wire to be applied to the bobbin except at a final assembly station. The method is most advantageously employed to the winding of wire on a series of bobbins which advance stepwise through a series of stations in such a fashion that each station is always occupied.

The invention further contemplates the provision of novel apparatus for carrying out the method of assembling and winding gages in a continual process. In general, the apparatus includes a fixture for receiving a series of bobbins at spaced locations and for advancing each bobbin through a series of work stations where various functions are performed. Wire from a substantially continuous supply such as a reel is payed out through a fiyer which winds coils of wire about each bobbin in series in such a manner as to eliminate the necessity of breaking the wire except at a final assembly station.

In a specific form of the invention, means are also provided for guiding the wire adjacent respective bobbin terminal posts prior to and subsequent to the coil winding step such that the normal advancement of the assembly function makes an electrical connection between respective ends of the coil or coils and the electrical terminals.

3,409,980 Patented Nov. 12, 1968 In a still further form of the invention, means are provided for removing insulation from the wire at predetermined locations which are calculated to come adjacent the terminals during the assembly procedure.

The novel method and apparatus may be best understood by reference to the description of a specific embodiment. Such a description is to be found in the following specification which specification is to be taken with the accompanying drawings of which:

FIGURE 1 is a perspective view of assembly apparatus according to a specific embodiment of the invention;

FIGURE 2 is a view of a portion of the apparatus of FIGURE 1 showing a first step to be performed in a specific example of the assembly method;

FIGURE 3 illustrates a second step in the specific example;

FIGURE 4 illustrates a third step in the specific example;

FIGURE 5 illustrates a fourth step in the specific example;

FIGURE 6 illustrates a fifth step in the specific example;

FIGURE 7 illustrates a sixth step in the specific example;

FIGURE 8 illustrates a seventh step in the specific example; and

FIGURE 9 illustrates an eighth and final step in the specific example.

Referring specifically to FIGURE 1, the apparatus involved in carrying out the invention is shown to include an indexable fixture which may be a turntable 10 adapted for continual or indexed rotation in a clockwise direction as indicated. The turntable 10 further includes a plurality of radially extending arms 12, 14, 16, 18, and 22 which are circumferentially and uniformly spaced about the turntable 10. Each of these arms is rotatable with turntable 10 and is adapted to receive and hold a coil bobbin 24 for advancement of the bobbin through a series of stations at which the various functions involved in assembling a gage in accordance with the specific embodiment of the invention are to be performed. It will be appreciated that the turntable 10, being provided with six bobbin mounting locations, is to be indexed or advanced in six discrete steps duringeach full cycle.

The bobbin 24 comprises a fiat central section 25 which may house a rotatable magnetic armature (not shown). Surrounding the central section 25 are four posts 26, 27, 28 and 29 of which posts 27 and 29 are shown to be provided with metallic terminals 30 and 32. Post 26 is empty thus to provide a convenient means for attachment to the radial arms of the turntable 10. An axle 31 for the armature protrudes from the central section 25 for hte mounting of an indicator needle following the coil winding and connecting procedure.

In the specific embodiment shown in the drawings, a single coil comprising several turns of wire is to be wound about the central section 25 of each of the bobbins 24. This winding is performed by means of a rotatable fiyer 34 which is provided with a wheel 36 for paying out enameled conductive wire 38 under tension from a wire supply reel (not shown).

The apparatus shown in FIGURE 1 further includes a wire guide post 40 which is adapted to be displaced by means such as an air cylinder into engagement with terminal 32 for guiding the tensioned wire 38 over and around the terminal 32 prior to winding the initial turn of wire about the bobin 24. A further wire guide finger 42 is also provided for moving the wire into engagement with terminal 30 subsequent to the winding of the final turn of wire about the bobbin 24. The use of enamel or other insulation on the wire 38 requires the removal of insulation prior to making contact between the wire and the terminals 30 and 32. Accordingly, a pair of gas torches 44 and 46 are placed at strategic locations and are energizable to burn insulation from specific locations on the wire selected to correspond with the points of electrical connection with terminals 30 and 32.

It can be seen in FIGURE 1 that moving clockwise from the station identified in the drawings by arm 18, each bobbin 24 advances through three additional stations, and further that the wire as payed out from flyer 34 extends between the bobbins at each of the next two locations, i.e., those shown in the drawings inhabited by arms 20 and 22. Accordingly, the bobbins are serially wound without the requirement for wire terminating apparatus except at the station which corresponds to the illustrated position of arm 22. At this station a pair of rotating wire cutters and wrappers 48 and 50 is provided. As better shown in FIG- URE 7, the cutters and wrappers 50 are located immediately above the terminals 30 and 32. The cutters and wrappers may be lowered over the terminals 30 and 32 by means of an air cylinder and the cutting blades rotated in the proper direction to terminate the wire 38 and wrap it snugly about terminals 30 and 32. The cutters and wrappers 48 and 50 operate in conjunction with a lower cutoff die 52 which may be raised by means of an air cylinder at the same time the above fixtures are lowered.

In the following description, the various stations through which each bobbin is advanced will be identified by the corresponding arm number appearing in FIGURE 1. While this is done to facilitate the explanation, it is to be understood that the arms 12, 14, 16, 18, 20 and 22 are actually rotated with the turntable 10.

Referring now to the additional figures, the steps involved with assembling a gage in accordance with the invention will be described in detail.

In FIGURE 1, an empty bobbin 24 carried by radially extending arm 18 has been rotated by a turntable into position between the gas torches 44 and 46 and adjacent the flyer 34. At this point the wire guide post 40 and guide finger 42 are in a withdrawn position and the flyer 34 is in a twelve oclock or straight up position. Wire 38 from the flyer 34 extends under slight tension leftward as shown in the drawings from the wheel 36 to the terminal posts of the previously wound bobbin on arm 20. In this position the wire 38 is stretched in front of the gas torch 44. As shown in FIGURE 2, gas is fed to torch 44 and ignited by means of an electrical igniter to produce a timed flame which is directed at a specific location on the wire 38 to remove insulation therefrom. Following the removal of insulation, the wire guide post 40 is displaced downwardly as shown in FIGURE 3 into engagement with terminal 32. The wire guide post is therefore outside, that is, toward the observer, as shown in the drawings, of the wire 38. Accordingly, as shown in FIG- URE 3, when the flyer 34 is rotated through 90 in a counterclockwise direction, the wire 38 slides down guide post 40 and around the terminal post 32. Continued counterclockwise rotation of the flyer 34 is effective to wrap or wind additional turns of Wire 38 about the central section of the bobbin 24 to form a coil.

As shown in FIGURES 4 and 5, at the completion of the winding the flyer 34 is brought to rest in a twelve oclock or straight up position. At this point wire guide finger 42 is advanced by means of an air cylinder such that the finger is brought into engagement with the upright portion of wire 38 between the completed coil and the wheel 36 of flyer 34. At this point torch 46 is ignited to remove insulation from a second portion of the wire 38 as shown in FIGURE 4.

Moving to FIGURE 5, the guide post 40 is retracted out of engagement with terminal 32, and the guide finger 42 is advanced to urge the wire 38 into engagement with terminal 30. As shown in FIGURE 6, advancement of the turntable 10 to the next position in a clockwise direction causes the wire 38 to be snugly hooked around terminal 30.

The advancement of turntable 10 also causes wire 38 to be payed out under tension through the flyer 34 from the wire supply reel.

After an intenmediate stop at the position represented by arm 20 in FIGURE 1, each bobbin is then advanced to the station which is represented by arm 22 in FIGURE 1. Referring to FIGURE 7, the position of bobbin 24 in FIG- URE' 7 is directly beneath the wire cutters and wrappers 48 and 50 and directly above the lower cutolf die 52. As shown in FIGURE 8, means such as an air cylinder may be provided to raise the cutoff die 52 and lower the cutters and wrappers 48 and 50 into engagement with the terminals 30 and 32 of the bobbin 24. Rotation of the cutters and wrappers 48 and 50 as shown in FIGURE 8 is effective to terminate and 'wrap the wire about the terminals 30 and 32 of the bobbin 24. As shown in FIGURE 9, the cutters and wrappers are withdrawn and following this step turntable 10 is advanced to bring the assembled gage to the station represented by arm 12 in FIGURE 1. At this point an operator may remove the bobbin from the arm 12 and replace it with an empty bobbin to be circulated through the process described above.

During the indexing process, turntable 10 rotates each bobbin to the station identified by arm 20 in FIGURE 1 intermediate the work stations identified by arms 18 and 22 in FIGURE 1. Therefore, the cutting step which takes place at the station identified by arm 22 does not release the tension on the portion of wire 38 which extends past the torch 44. Tension is released on the portion of wire extending between the bobbins located at arms 22 and 20. However, this is of no consequence since the process of winding and hooking of the wire around the terminals has been completed at arm 20.

It is to be understood that the invention has been described with particular reference to a specific embodiment thereof, and that various modifications will be apparent to those skilled in the art without departing from the spirit and scope of the invention. For a definition of the inven tion, reference should be made to the appended claims.

We claim:

1. Apparatus for continually winding coils of wire on a series of bobbins each having at least two extending terminals comprising: a supply of wire, indexable turntable support means having a plurality of fixtures for receiving said bobbins and displacing said bobbins through a series of spaced stations, at flyer at a first station for coiling wire from the supply about each bobbin in series, a guide post at the first station selectively engageable with one terminal for placing a portion of wire preceding said coils over said one terminal when said flyer is ro-v tated, a guide finger at the first station selectively engageable with the other terminal for placing a portion of wire following said coils proximate said other terminal, a second station following the first station in the normal advancement of said support means, means at said second station for wrapping and severing said wire, and a third station intermediate the first and second stations at which the bobbin, intermediate the bobbins at stations one and two, is held for the purpose of maintaining tension in the wire at the first station after said wire is severed at the second station.

2. Apparatus defined in claim 1 further including means located at the first station for removing insulation from portions of the wire contacting the terminals.

3. A method for continuousy winding coils of insulated wire onto a sequentially supplied plurality of indi vidual bobbins having terminal posts and making electrical connections thereto comprising the steps of mounting the individual bobbins at spaced locations on an indexable turtable, rotating the turntable to a first position wherein a first bobbin is adjacent a flyer loaded with a continuous supply of insulated wire, removing a first portion of insulation from said wire, engaging a terminal post of the bobbin with a wire guide, rotating the flyer to wrap the uninsulated portion of wire around the terminal post under the direction of the guide, disengaging the guide, continuing to rotate the flyer to wrap turns of wire around the bobbin, stopping the fiyer with the wire extending from the bobbin to the flyer adjacent another terminal post, removing insulation from a second portion of wire, urging the uninsulated portion of wire into enthe turntable to a second position simultaneously to hook said portion of wire around the second post, rotating the turntable to a third position such that following bobbins oecupy the first and second positions, wrapping and cutting the wire portions at the terminal posts of the bobbin in the third position, and removing the completed bobbins and continuing said operations.

References Cited UNITED STATES PATENTS Cerny 29-618 Kirsch 29-596 X Eminger 2421.1 Basile et a1. 1401 Ganci 29-618 Cartwright et a1 242-9 X 10 JOHN F. CAMPBELL, Primary Examiner.

C. E. HALL, Assistant Examiner. 

